Extract a common base class for public key serializers/deserializers

service/src/main/java/org/whispersystems/textsecuregcm/util/AbstractPublicKeyDeserializer.java

@@ -0,0 +1,35 @@
+package org.whispersystems.textsecuregcm.util;
+
+import com.fasterxml.jackson.core.JsonParseException;
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.databind.DeserializationContext;
+import com.fasterxml.jackson.databind.JsonDeserializer;
+import java.io.IOException;
+import java.util.Base64;
+import org.signal.libsignal.protocol.InvalidKeyException;
+
+abstract class AbstractPublicKeyDeserializer<K> extends JsonDeserializer<K> {
+
+  @Override
+  public K deserialize(final JsonParser parser, final DeserializationContext context) throws IOException {
+    final byte[] publicKeyBytes;
+
+    try {
+      publicKeyBytes = Base64.getDecoder().decode(parser.getValueAsString());
+    } catch (final IllegalArgumentException e) {
+      throw new JsonParseException(parser, "Could not parse public key as a base64-encoded value", e);
+    }
+
+    if (publicKeyBytes.length == 0) {
+      return null;
+    }
+
+    try {
+      return deserializePublicKey(publicKeyBytes);
+    } catch (final InvalidKeyException e) {
+      throw new JsonParseException(parser, "Could not interpret key bytes as a public key", e);
+    }
+  }
+
+  protected abstract K deserializePublicKey(final byte[] publicKeyBytes) throws InvalidKeyException;
+}

service/src/main/java/org/whispersystems/textsecuregcm/util/AbstractPublicKeySerializer.java

@@ -0,0 +1,20 @@
+package org.whispersystems.textsecuregcm.util;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.JsonSerializer;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import java.io.IOException;
+import java.util.Base64;
+
+abstract class AbstractPublicKeySerializer<K> extends JsonSerializer<K> {
+
+  @Override
+  public void serialize(final K publicKey,
+      final JsonGenerator jsonGenerator,
+      final SerializerProvider serializerProvider) throws IOException {
+
+    jsonGenerator.writeString(Base64.getEncoder().encodeToString(serializePublicKey(publicKey)));
+  }
+
+  protected abstract byte[] serializePublicKey(final K publicKey);
+}

service/src/main/java/org/whispersystems/textsecuregcm/util/ECPublicKeyAdapter.java

@@ -5,52 +5,24 @@
 
 package org.whispersystems.textsecuregcm.util;
 
-import com.fasterxml.jackson.core.JsonGenerator;
-import com.fasterxml.jackson.core.JsonParseException;
-import com.fasterxml.jackson.core.JsonParser;
-import com.fasterxml.jackson.databind.DeserializationContext;
-import com.fasterxml.jackson.databind.JsonDeserializer;
-import com.fasterxml.jackson.databind.JsonSerializer;
-import com.fasterxml.jackson.databind.SerializerProvider;
-import java.io.IOException;
-import java.util.Base64;
 import org.signal.libsignal.protocol.InvalidKeyException;
 import org.signal.libsignal.protocol.ecc.ECPublicKey;
 
 public class ECPublicKeyAdapter {
 
-  public static class Serializer extends JsonSerializer<ECPublicKey> {
+  public static class Serializer extends AbstractPublicKeySerializer<ECPublicKey> {
 
     @Override
-    public void serialize(final ECPublicKey ecPublicKey,
+    protected byte[] serializePublicKey(final ECPublicKey publicKey) {
-        final JsonGenerator jsonGenerator,
+      return publicKey.serialize();
-        final SerializerProvider serializers) throws IOException {
-
-      jsonGenerator.writeString(Base64.getEncoder().encodeToString(ecPublicKey.serialize()));
     }
   }
 
-  public static class Deserializer extends JsonDeserializer<ECPublicKey> {
+  public static class Deserializer extends AbstractPublicKeyDeserializer<ECPublicKey> {
 
     @Override
-    public ECPublicKey deserialize(final JsonParser parser, final DeserializationContext context) throws IOException {
+    protected ECPublicKey deserializePublicKey(final byte[] publicKeyBytes) throws InvalidKeyException {
-      final byte[] ecPublicKeyBytes;
+      return new ECPublicKey(publicKeyBytes);
-
-      try {
-        ecPublicKeyBytes = Base64.getDecoder().decode(parser.getValueAsString());
-      } catch (final IllegalArgumentException e) {
-        throw new JsonParseException(parser, "Could not parse EC public key as a base64-encoded value", e);
-      }
-
-      if (ecPublicKeyBytes.length == 0) {
-        return null;
-      }
-
-      try {
-        return new ECPublicKey(ecPublicKeyBytes);
-      } catch (final InvalidKeyException e) {
-        throw new JsonParseException(parser, "Could not interpret identity key bytes as an EC public key", e);
-      }
     }
   }
 }

service/src/main/java/org/whispersystems/textsecuregcm/util/KEMPublicKeyAdapter.java

@@ -5,52 +5,24 @@
 
 package org.whispersystems.textsecuregcm.util;
 
-import com.fasterxml.jackson.core.JsonGenerator;
-import com.fasterxml.jackson.core.JsonParseException;
-import com.fasterxml.jackson.core.JsonParser;
-import com.fasterxml.jackson.databind.DeserializationContext;
-import com.fasterxml.jackson.databind.JsonDeserializer;
-import com.fasterxml.jackson.databind.JsonSerializer;
-import com.fasterxml.jackson.databind.SerializerProvider;
 import org.signal.libsignal.protocol.InvalidKeyException;
 import org.signal.libsignal.protocol.kem.KEMPublicKey;
-import java.io.IOException;
-import java.util.Base64;
 
 public class KEMPublicKeyAdapter {
 
-  public static class Serializer extends JsonSerializer<KEMPublicKey> {
+  public static class Serializer extends AbstractPublicKeySerializer<KEMPublicKey> {
 
     @Override
-    public void serialize(final KEMPublicKey kemPublicKey,
+    protected byte[] serializePublicKey(final KEMPublicKey publicKey) {
-        final JsonGenerator jsonGenerator,
+      return publicKey.serialize();
-        final SerializerProvider serializers) throws IOException {
-
-      jsonGenerator.writeString(Base64.getEncoder().encodeToString(kemPublicKey.serialize()));
     }
   }
 
-  public static class Deserializer extends JsonDeserializer<KEMPublicKey> {
+  public static class Deserializer extends AbstractPublicKeyDeserializer<KEMPublicKey> {
 
     @Override
-    public KEMPublicKey deserialize(final JsonParser parser, final DeserializationContext context) throws IOException {
+    protected KEMPublicKey deserializePublicKey(final byte[] publicKeyBytes) throws InvalidKeyException {
-      final byte[] kemPublicKeyBytes;
+      return new KEMPublicKey(publicKeyBytes);
-
-      try {
-        kemPublicKeyBytes = Base64.getDecoder().decode(parser.getValueAsString());
-      } catch (final IllegalArgumentException e) {
-        throw new JsonParseException(parser, "Could not parse KEM public key as a base64-encoded value", e);
-      }
-
-      if (kemPublicKeyBytes.length == 0) {
-        return null;
-      }
-
-      try {
-        return new KEMPublicKey(kemPublicKeyBytes);
-      } catch (final InvalidKeyException e) {
-        throw new JsonParseException(parser, "Could not interpret key bytes as a KEM public key", e);
-      }
     }
   }
 }